CentOS7.6部署k8s环境

CentOS7.6部署k8s环境

测试环境：

节点名称	节点IP	节点功能
K8s-master	10.10.1.10/24	Master、etcd、registry
K8s-node-1	10.10.1.20/24	node-1
K8s-node-2	10.10.1.30/24	node-2

步骤：

1. 修改hosts文件

[root@Node-1 ~]# hostnamectl --static set-hostname  k8s-master

[root@Node-1 ~]# vi /etc/hosts

10.10.1.10    k8s-master

10.10.1.10   etcd

10.10.1.10   registry

10.10.1.20   k8s-node-1

10.10.1.30   k8s-node-2

1. 部署etcd(注：本次只master节点安装etcd)

[root@node-1 ~]#  yum install etcd –y

[root@node-1 ~]# vi /etc/etcd/etcd.conf

#[Member]

#ETCD_CORS=""

ETCD_DATA_DIR="/var/lib/etcd/default.etcd"

#ETCD_WAL_DIR=""

#ETCD_LISTEN_PEER_URLS="http://localhost:2380"

ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"

ETCD_NAME="master"

#[Clustering]

#ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost:2380"

ETCD_ADVERTISE_CLIENT_URLS=http://etcd:2379,http://etcd:4001

启动服务

[root@node-1 ~]# systemctl start etcd.service

[root@node-1 ~]# systemctl enable etcd.service

验证集群状态

[root@node-1 ~]#  etcdctl -C http://etcd:4001 cluster-health

member 8e9e05c52164694d is healthy: got healthy result from http://etcd:2379

cluster is healthy

[root@node-1 ~]#

1. 部署master

3.1.安裝docker

[root@node-1 ~]# yum install docker

[root@node-1 ~]# vi /etc/sysconfig/docker

# /etc/sysconfig/docker

# Modify these options if you want to change the way the docker daemon runs

OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false'

if [ -z "${DOCKER_CERT_PATH}" ]; then

DOCKER_CERT_PATH=/etc/docker

fi

OPTIONS='--insecure-registry registry:5000'

3.2.启动docker服务并设置开机启动

[root@node-1 ~]# systemctl start docker.service

[root@node-1 ~]# systemctl enable docker.service

3.3.安裝kubernets

[root@node-1 ~]# yum install kubernetes

3.4. 配置并且启动kubernets服务(该步骤只在master节点)

Kubernets API Server

Kubernets Controller Manager

Kubernets Scheduler

[root@node-1 ~]# vi /etc/kubernetes/apiserver

# kubernetes system config

#

# The following values are used to configure the kube-apiserver

#

# The address on the local server to listen to.

KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"

# The port on the local server to listen on.

KUBE_API_PORT="--port=8080"

# Port minions listen on

# KUBELET_PORT="--kubelet-port=10250"

# Comma separated list of nodes in the etcd cluster

KUBE_ETCD_SERVERS="--etcd-servers=http://etcd:2379"

# Address range to use for services

KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"

# default admission control policies

#KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"

KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"

# Add your own!

KUBE_API_ARGS=""

[root@node-1 ~]# vi /etc/kubernetes/config

# How the controller-manager, scheduler, and proxy find the apiserver

KUBE_MASTER="--master=http://k8s-master:8080"

3.5. 启动服务并设置开机启动

[root@k8s-master ~]# systemctl enable kube-apiserver.service

[root@k8s-master ~]# systemctl start kube-apiserver.service

[root@k8s-master ~]# systemctl enable kube-controller-manager.service

[root@k8s-master ~]# systemctl start kube-controller-manager.service

[root@k8s-master ~]# systemctl enable kube-scheduler.service

[root@k8s-master ~]# systemctl start kube-scheduler.service

1. 部署节点

4.1.部署和3.1-3.3相同

4.2.修改配置文件

[root@Node-2 ~]# vi /etc/kubernetes/config

# How the controller-manager, scheduler, and proxy find the apiserver

KUBE_MASTER="--master=http://k8s-master:8080"

[root@Node-2 ~]# vi //etc/kubernetes/kubelet

KUBELET_ADDRESS="--address=0.0.0.0"

KUBELET_HOSTNAME="--hostname-override=k8s-node-1"

KUBELET_API_SERVER="--api-servers=http://etcd:8080"

4.3.启动服务并设置开机启动

[root@k8s-node-1 ~]# systemctl enable kubelet.service

[root@k8s-node-1 ~]# systemctl start kubelet.service

[root@k8s-node-1 ~]# systemctl enable kube-proxy.service

[root@k8s-node-1~]# systemctl start kube-proxy.service

1. 查看群集状态

[root@k8s-master ~]# kubectl get node

NAME         STATUS     AGE

k8s-node-1   Ready      14h

k8s-node-2   Ready      14h

1. 安装Flannel(所有节点)

[root@node-1 ~]# yum install flannel

[root@node-1 ~]# vi /etc/sysconfig/flannel

# Flanneld configuration options

# etcd url location.  Point this to the server where etcd runs

FLANNEL_ETCD_ENDPOINTS="http://etcd:2379"

# etcd config key.  This is the configuration key that flannel queries

# For address range assignment

FLANNEL_ETCD_PREFIX="/atomic.io/network"

1. 配置etcd中关于flannel的key

[root@node-1 ~]#  etcdctl mk /atomic.io/network/config '{ "Network": "10.0.0.0/16" }'

设置flannel服务启动和开机启动：

[root@node-1 ~]# systemctl enable flanneld.service

[root@node-1 ~]# systemctl start flanneld.serivice

管理节点执行：

service docker restart

systemctl restart kube-apiserver.service

systemctl restart kube-controller-manager.service

systemctl restart kube-scheduler.service

业务节点执行

service docker restart

systemctl restart kubelet.service

systemctl restart kube-proxy.service

业务节点拉取image

[root@Node-2 ~]# docker pull winstonpro/lnmp

[root@Node-2 ~]# docker pull tomcat

[root@Node-2 ~]# docker pull httpd

管理节点创建实例

kubectl run web --image=winstonpro/lnmp --port=80

管理节点做svc映射

kubectl expose deployment web --port=80 --target-port=80 --external-ip=10.10.1.30

常用命令：

[root@node-1 ~]# kubectl get node -o wide

NAME         STATUS     AGE       EXTERNAL-IP

k8s-node-1   Ready      14h       <none>

k8s-node-2   Ready      14h       <none>

[root@node-1 ~]# kubectl get pod -o wide

NAME                      READY     STATUS    RESTARTS   AGE       IP          NODE

app-556711052-ps9kr       1/1       Running   3          7h        10.0.53.2   k8s-node-1

tomcat-3343039334-0z187   1/1       Running   0          2h        10.0.74.3   k8s-node-2

web-3818241055-g11q8      1/1       Running   3          8h        10.0.74.2   k8s-node-2

[root@node-1 ~]# kubectl get svc -o wide

NAME         CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE       SELECTOR

kubernetes   10.254.0.1      <none>        443/TCP    15h       <none>

tomcat       10.254.69.86    10.10.1.30    7777/TCP   2h        run=tomcat

web          10.254.76.251   10.10.1.30    80/TCP     6h        run=web

[root@node-1 ~]# kubectl get  deployments

NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE

app       1         1         1            1           7h

tomcat    1         1         1            1           2h

web       1         1         1            1           8h

关于外网无法访问：

[root@Node-2 ~]# vi /etc/sysctl.conf

net.ipv4.ip_forward = 1

[root@Node-2 ~]# sysctl -p

iptables -P INPUT ACCEPT

iptables -P FORWARD ACCEPT

iptables -F